Method of delustering fabric and product thereof



Patented May 6, 1930 UNITED STATES CAMILLE DREYFUS, OF NEW YORK, N. Y.,

AND HERBERT PLATT, OF CUMBERLAND,

MARYLAND, ASSIGNORS TO CELANESE CORPORATION OF AMERICA, A CORPORATION OF DELAWARE METHOD OF DELUSTERING FABRIC AND PRODUCT THEREOF No Drawing.

This invention relates to the treatment of textile materials containing organic derivatives of cellulose so as to subdue the luster of the same.

An object of our invention is to reduce the luster of textile materials containing organic derivatives of cellulose in such a manner that the delustering effect is comparatively permanent.

Another object of our invention is to deluster textile materials containing organic derivatives of cellulose by precipitating zinc sulphide, as an opaque insoluble salt, in the textile material. Other objects of our invention will appear from the following detailed description.

Heretofore textile materials containing organic derivatives or cellulose, such as cellulose acetate, have been delustered by boiling water, wet steam or aqueous solutions of various reagents. However, the delustering effect produced by such processes is not permanent and such delustered fabrics regain all or part of their luster when they are ironed while damp. or subjected to dry steam or other agencies. Obviously this tendency to reluster is a serious drawback.

We have found that practically permanent subdued luster may be imparted to an organic derivative of cellulose material by precipitating zinc sulphide in the form of an opaque insoluble salt throughout and within the fibres of the yarn of the organic ester of cellulose.

In accordance with our invention we treat a textile material containing organic derivatives of cellulose with a solution of a soluble zinc salt. which is itself a swelling agent for the organic derivatives of cellulose, or in the presence of a foreign swelling agent, and then treat the same with a solution that contains sulphide ions and that is adapted to precipitate the zinc in the form of the opaque and white zinc sulphide.

The textile material to be treatedin accordance with our invention may be in the form of yarns in a suitable package such as hanks. on bobbins. etc. However, we prefer to treat a fabric containing yarns of such organic derivatives of cellulose. These or- Application filed December 27, 1928. Serial No. 328,847.

ganic derivatives of cellulose may be organic esters of cellulose or cellulose ethers. Examples of organic derivatives of cellulose are cellulose acetate, cellulose formate, cellulose propionate and cellulose butyrate while examples of cellulose ethers are ethyl cellulose, methyl cellulose and benzyl cellulose. The fabric need not consist wholly of yarns of such organic derivatives but may also contain yarns of other materials such as cotton, artificial silks of reconstituted cellulose, silk, wool, etc.

Any suitable soluble salt of zinc maybe employed in the solution, such as zinc chloride, zinc sulphate, etc. The solutions of such zinc may be of themselves swelling agents. Thus zinc chloride in sufliciently concentrated solutions acts as a swelling agent for cellulose acetate. If the zinc salt is not a swelling agent or is employed in low concentrations so that the solutions are not swelling agents, foreign swelling agents may be added to the above. Examples of such foreign swelling agents are formic acid, acetic acid, acetone, etc. If desired, the textile material may be first treated with a bath containing these swelling agents. and then with a bath containing the zinc salts.

After treatment with the solutions of the zinc salts, the textile material is then treated with a solution that contains sulphide ions that is adapted to precipitate the zinc in the v form of zinc sulphide. While we prefer to use solutions of the sulphides of the alkali metals such as sodium sulphide, potassium sulphide or ammonium sulphide, a solution of hydrogen sulphide may be employed either in the presence of an acid or in the absence thereof, provided the solution is not of such great acidity that the precipitation of zinc sulphide is inhibited.

Because of the action of the swelling a ent, the zinc salts permeate throughout the bres and are generally retained therein so that when they are precipitated as the-zinc sulphide they will not wash out.

The textile materials produced by our invention have asubdued luster varying from complete deluster to partial deluster depend ing on the concentration and the time of treatment, and temperatures, which control the amount of zinc sulphide that is precipitated inthe .fiber and this deluster effect is substantially permanent. Fabrics when treated by our invention may be ironed while 'damp or subjected to dry steam or other relustering agents without becoming relustered.

Moreover, fabrics, when treated by our invention, have a very soft handle.

To obtain further desirable efiects, the textile material to be treated by our invention may be partially saponified, and particularly intensely surface saponified. By this is meant treatment with alkaline solutions in such concentrations and in such manner that substantially only the outer layer of the fibres of cellulose ester material is saponified, while basic dyestuffs, and also have an increased affinity for direct cotton colors and for acid colors.

. In order further to illustrate our invention,

the following specific examples are given.

Example I This'is an example wherein the fabric is treated witha solution of zinc chloride of i such concentration that it is of itself a swelling agent.

A fabric consisting wholly of yarns of cellulose acetate is padded in a bath containing Parts by weight Water 750 Zinc chloride 320 This bath is maintained at a temperature of C. The padded fabric is allowed to stand over night andis then padded with a solution of sodium sulphide of 2% concentration at 30 C. The fabric is then rinsed,

scoured with soap and washed in order to 'remove the soap. A very satisfactory delustered fabric is thus produced.

Ewcmple [I i The following is an example of our invention where an extraneous swelling agent, which in this case is formic acid, is employed.

A fabric consisting wholly of yarns of cellulose acetate is padded in a bath containing Parts by weight Water -i 750 Zinc chloride 250 Formic acid 100 The temperature of the bath is 70 C. The padded fabric is allowed to stand over night, and is then padded in a bath containing sodium sulphide of 2% concentration at 30 C. The fabric is then rinsed, scoured with soap and washed. The fabric thus produced has the zinc sulphide distributed therein and is evenly delustered.

It is to be understood that the foregoing detailed description is given merely by way of illustration and that many variations may be made therein without departing from the spirit of our invention.

Having described our invention what we claim and desire to secure by Letters Patent 1. Method of treating textile materials containing organic derivatives of cellulose comprising precipitating zinc sulphide within the fibres of such textile materials.

2. Method of treating textile materials containing cellulose acetate comprising precipitating zinc sulphide within the fibres of such textile materials.

3. Method of producing the relatively subdued luster on a fabric containing yarns of organic derivatives of cellulose comprising treating such fabric in a bath that acts as a swelling agent for the organic derivative of cellulose, which bath contains a soluble salt of zinc, and then-treating the fabric'with a reagent that precipitates the zinc in the form of zinc sulphide.

4. Method of producing the relatively subdued luster on a fabric containing yarns of cellulose acetate comprising treating such fabric in a bath that acts as a swelling agent for the cellulose acetate which bath contains a soluble salt of zinc, and then treating the fabric with a reagent that precipitates the zinc in the form of zinc sulphide.

5. Method of producing the relatively subdued luster on a fabric containing yarns of organic derivatives of cellulose comprising treating such fabric in a bath that acts as a swelling agent for the organic derivatives of cellulose, which bath contains a'soluble salt of zinc, and then treating the fabric with a solution of a soluble sulphide, whereby zinc sulphide is precipitated.

6. Method of producing the relatively subdued luster on a fabric containing yarns of cellulose acetate comprising treating such fabric in a bath that acts as a swelling agent for the cellulose acetate which bath contains a sol-.

uble salt of zinc, and then treatin the fabric with a solution of a soluble sulphi e, whereby zinc sulphide is precipitated.

7. Method of treating fabrics containing yarns of organic derivatives of cellulose comprising treating said fabric with a solution of zinc chloride and then treating the fabric with a solution containing sulphide ions.

8. Method of treating fabrics containing yarns of cellulose acetate comprising treating said fabric with a solution of zinc chloride and then treating the fabric with a solution containing sulphide ions.

9. A textile material containing organic derivatives of cellulose, which textile material has a subdued luster and contains zinc 'sulphide.

10. A textile material containing cellulose acetate, which textile material has a. subdued luster and contains zinc sulphide.

In testimony whereof, we have hereunto subscribed our names.

CAMILLE DREYFUS. HERBERT PLATT. 

